We have drafted a protocol and planned staffing for LIFE-Moms-Phoenix, which will be a randomized clinical trial in overweight and obese pregnant women with the objective of testing the effects of an intensive lifestyle intervention on optimizing gestational weight gain, control of maternal hyperglycemia, and post-partum return to pre-pregnancy weight. The Phoenix center will be conducted in collaboration between the Phoenix Indian Medical Center (PIMC) nurse midwifery and obstetrics services and the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). It is part of the LIFE-Moms Consortium consisting of six other clinical centers that will follow similar protocols and a research coordination unit. Participant enrollment should begin during the coming year.